Remove mentions of QtConcurrent::runWithPromise from docs

cf043a785a unified QtConcurrent::run() and
QtConcurrent::runWithPromise(). Remove the last mentions of
runWithPromise. Also did some minor cosmetic improvements.

Pick-to: 6.3
Change-Id: Ie3b39600978ccfa4a009d3ff68567a348dc7b166
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
Reviewed-by: Jarek Kobus <jaroslaw.kobus@qt.io>
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@qt.io>

src/concurrent/qtconcurrentrun.cpp

@@ -167,18 +167,17 @@
 
     \section2 The mandatory QPromise argument
 
-    The function passed to QtConcurrent::run() in \e {Run With Promise} mode is expected
-    to have an additional argument of \c {QPromise<T> &} type, where
-    T is the type of the computation result (it should match the type T
-    of QFuture<T> returned by the QtConcurrent::runWithPromise()), like e.g.:
+    The function passed to QtConcurrent::run() in \e {Run With Promise} mode
+    is expected to have an additional argument of \c {QPromise<T> &} type, where
+    \c T is the type of the computation result (it should match the type \c T
+    of QFuture<T> returned by QtConcurrent::run()), like e.g.:
 
     \snippet code/src_concurrent_qtconcurrentrun.cpp 9
 
-    The \c promise argument is instantiated inside the
-    QtConcurrent::run() function, and its reference
-    is passed to the invoked \c aFunction, so the user
-    doesn't need to instantiate it by himself, nor pass it explicitly
-    when calling QtConcurrent::runWithPromise().
+    The \c promise argument is instantiated inside the QtConcurrent::run()
+    function, and its reference is passed to the invoked \c aFunction, so the
+    user doesn't need to instantiate it, nor pass it explicitly
+    when calling QtConcurrent::run() in this mode.
 
     The additional argument of QPromise type always needs to appear
     as a first argument on function's arguments list, like:

src/concurrent/qtconcurrentrun.h

@@ -61,12 +61,6 @@ namespace QtConcurrent {
     template <typename T>
     QFuture<T> run(QThreadPool *pool, Function function, ...);
 
-    template <typename T>
-    QFuture<T> runWithPromise(Function function, ...);
-
-    template <typename T>
-    QFuture<T> runWithPromise(QThreadPool *pool, Function function, ...);
-
 } // namespace QtConcurrent
 
 #else

src/corelib/thread/qpromise.qdoc

@@ -83,7 +83,9 @@
 
     \internal
     Constructs a QPromise with a passed QFutureInterface \a other.
-    Used internally for QtConcurrent::runWithPromise.
+    Used internally for QtConcurrent::run(), when its callable takes
+    a reference to the associated promise as its first argument
+    (run with promise mode).
 
     \sa operator=()
 */